SB2023072073 - Gentoo update for OpenSSH



SB2023072073 - Gentoo update for OpenSSH

Published: July 20, 2023 Updated: January 9, 2026

Security Bulletin ID SB2023072073
Severity
High
Patch available
YES
Number of vulnerabilities 3
Exploitation vector Remote access
Highest impact Code execution

Breakdown by Severity

High 33% Medium 33% Low 33%
  • Low
  • Medium
  • High
  • Critical

Description

This security bulletin contains information about 3 secuirty vulnerabilities.


1) Double Free (CVE-ID: CVE-2023-25136)

The vulnerability allows a remote attacker to potentially execute arbitrary code on the target system.

The vulnerability exists due to a boundary error within the sshd(8) daemon. A remote non-authenticated attacker can send  specially crafted data to the application, trigger a double free error and execute arbitrary code on the target system.

The vendor believes exploitation of this vulnerability has limitations as double free occurs "in the unprivileged pre-auth process that is subject to chroot(2) and is further sandboxed on most major platforms". Nevertheless we assign a high risk to this vulnerability.


2) Credentials management (CVE-ID: CVE-2023-28531)

The vulnerability allows a remote user to bypass implemented security restrictions.

the vulnerability exists due to a logic error in ssh-add when adding smartcard keys to ssh-agent with the per-hop destination constraints. As a result, the keys are added without constraints.


3) Untrusted search path (CVE-ID: CVE-2023-38408)

The vulnerability allows a remote attacker to compromise the affected system.

The vulnerability exists due to usage of an insecure search path within the PKCS#11 feature in ssh-agent. A remote attacker can trick the victim into connecting to a malicious SSH server and execute arbitrary code on the system, if an agent is forwarded to an attacker-controlled system.

Note, this vulnerability exists due to incomplete fix for #VU2015 (CVE-2016-10009).


Remediation

Install update from vendor's website.